Answer:
18 g is the mass produced by 4 g of H₂ and 16 g of O₂
Explanation:
The reaction is:
2H₂ + O₂ → 2H₂O
So, let's find out the limiting reactant as we have both data from the reactants.
Mass / Molar mass = moles
4 g/ 2g/m = 2 moles H₂
16g / 32 g/m = 0.5 moles O₂
2 moles of hydrogen react with 1 mol of oxygen, but I have 0.5, so the O₂ is the limiting.
1 mol of O₂ produces 2 mol of water.
0.5 mol of O₂ produce (0.5 .2)/1 = 1 mol of water.
1 mol of water weighs 18 grams.
Answer:
Electrons
Explanation:
According to the Valence Shell Electron Pair Repulsion Theory (VSEPR), the geometry of a molecule depends on the number of electron pairs (regions of electron density) on the central atom of the molecule. Electron pairs on the valence shell of the molecule tend to position themselves as far apart in space as possible to minimize repulsion between them. Hence, the orientation of these electron pairs is the ultimate determinant of the observed geometry of a molecule.
Lone pairs of electrons cause more repulsion than bond pairs of electrons on the central atom of a molecule. Hence when the central atom of a molecule contains lone pairs of electrons, the molecular geometry is usually distorted from the expected geometry on the basis of VSEPR theory.
Hence, electrons are the subatomic particles which are responsible for any change in the observed molecular geometry of a molecule.
Mg (s) + 2 HCl (aq) -> MgCl2 (aq) + H2 (g)
1) Number of mols of HCl, n
n = 6.3 L * 4.5 mol/L = 28.35 mol
2) ratio: 2 mol HCl / 1 mol Mg = 28.35 mol HCl / x mol Mg
x = 28.35 mol HCL * 1 mol Mg / 2 mol HCL = 14.175 mol Mg
3) Convert mol to mass using atomic mass of Mg
14.175 mol Mg * 24.3 g Mg / mol Mg = 344. 45 g
Answer: 344.45 g
<h3>
Answer:</h3>
Seconds (s)
Liters (L)
<h3>
Explanation:</h3>
SI units relate to the International System of Units. These units are the base, metric units that are most commonly accepted for different measurements.
Common SI Units
The most common SI units are as follows:
- Length - meter (m)
- Time - second (s)
- Mass - kilogram (kg)
- Amount of substance - mole (mole)
- Electric current - ampere (A)
- Temperature - kelvin (K)
- Volume - liter (L)
*Note that gram (g) is not an SI unit
Each type of measurement will only have 1 SI unit. This is the unit that will be expected for most answers. Sometimes this means converting an answer into a different unit so it is more widely accepted.
Why SI Units are Important
SI units are important for the same reason that the metric system is used. It gives a standardized list of measurements that scientists across the world can use. Also, it makes it easier to compare scientific findings and studies when all of the measurements are given in the same units.
There are times when it is unrealistic to use SI units. For example, when discussing space, using meters will not be realistic due to the size of space. Also, when measuring the mass of small elements, kilograms are too large. But otherwise, SI units should be used.
